<template>
  <div class="detail">
    <Header></Header>
    <div class="main">
      <div class="course-info">
        <div class="wrap-left">
          <videoPlayer class="video-player vjs-custom-skin"
                       ref="videoPlayer"
                       :playsinline="true"
                       :options="playerOptions"
                       @play="onPlayerPlay($event)"
                       @pause="onPlayerPause($event)">
          </videoPlayer>
        </div>
        <div class="wrap-right">
          <h3 class="course-name">{{course.name}}</h3>
          <p class="data">{{course.students}}人在学&nbsp;&nbsp;&nbsp;&nbsp;课程总时长：{{course.lessons}}课时/{{course.lessons===course.pub_lessons?'更新完成':`已更新${course.pub_lessons}小时`}}&nbsp;&nbsp;&nbsp;&nbsp;难度：{{course.level_name}}</p>
          <div class="sale-time" v-if="course.discount_name">
            <p class="sale-type">{{course.discount_name}}</p>
            <p class="expire">距离结束：仅剩 {{course.active_time/60/60/24 | format_time}}天 {{course.active_time/60/60 % 24 |
              format_time}}小时 {{course.active_time/60 % 60 | format_time}}分 <span class="second">{{course.active_time % 60|format_time}}</span>
              秒</p>
            <!--              <p class="expire">距离结束：{{course.active_time}}秒</p>-->

          </div>
          <p class="course-price">
            <span v-if="course.discount_name">活动价</span>
            <span class="discount">¥{{course.real_price}}</span>
            <span class="original" v-if="course.discount_name">¥{{course.price}}</span>
          </p>
          <div class="buy">
            <div class="buy-btn">
              <button class="buy-now">立即购买</button>
              <button class="free">免费试学</button>
            </div>
            <div class="add-cart" @click="addCart"><img src="/static/image/cart-yellow.svg" alt="">加入预购课</div>
          </div>
        </div>
      </div>
      <div class="course-tab">
        <ul class="tab-list">
          <li :class="tabIndex==1?'active':''" @click="tabIndex=1">详情介绍</li>
          <li :class="tabIndex==2?'active':''" @click="tabIndex=2">课程章节 <span :class="tabIndex!=2?'free':''">(试学)</span>
          </li>
          <li :class="tabIndex==3?'active':''" @click="tabIndex=3">用户评论 (42)</li>
          <li :class="tabIndex==4?'active':''" @click="tabIndex=4">常见问题</li>
        </ul>
      </div>
      <div class="course-content">
        <div class="course-tab-list">
          <div class="tab-item" v-if="tabIndex==1">
            <!-- brief 字段在数据库中保存的是html标签 -->
            <div class='detail_img' v-html="course.brief_html">
            </div>
          </div>
          <div class="tab-item" v-if="tabIndex==2">
            <div class="tab-item-title">
              <p class="chapter">课程章节</p>
              <p class="chapter-length">共{{course_chapter.length}}章 {{course.lessons}}个课时</p>
            </div>
            <div class="chapter-item" v-for="(chapter,index) in course_chapter">
              <p class="chapter-title"><img src="/static/image/1.svg" alt="">第{{chapter.chapter}}章·{{chapter.name}}</p>
              <ul class="lesson-list">
                <li class="lesson-item" v-for="(lesson,i) in chapter.coursesections">
                  <p class="name"><span class="index">{{chapter.chapter}}-{{lesson.lesson}}</span>
                    课程介绍-{{lesson.name}}<span class="free" v-if="lesson.free_trail">免费</span></p>
                  <p class="time">{{lesson.duration}} <img src="/static/image/chapter-player.svg"></p>
                  <button class="try" v-if="lesson.free_trail">
                    <router-link to="/course/player">立即试学</router-link>
                  </button>
                  <button class="try" v-else>立即购买</button>
                </li>
              </ul>
            </div>
          </div>
          <div class="tab-item" v-if="tabIndex==3">
            用户评论
          </div>
          <div class="tab-item" v-if="tabIndex==4">
            常见问题
          </div>
        </div>
        <div class="course-side">
          <div class="teacher-info">
            <h4 class="side-title"><span>授课老师</span></h4>
            <div class="teacher-content">
              <div class="cont1">
                <img :src="course.teacher.image">

                <div class="name">
                  <p class="teacher-name">{{course.teacher.name}}</p>
                  <p class="teacher-title">{{course.teacher.title}}</p>
                </div>
              </div>
              <p class="narrative">{{course.teacher.brief}}</p>
            </div>
          </div>
        </div>
      </div>
    </div>
    <Footer></Footer>
  </div>
</template>

<script>
    import Header from "./common/Header"
    import Footer from "./common/Footer"
    import {videoPlayer} from 'vue-video-player';

    export default {
        name: "Detail",
        data() {
            return {
                course_id: 0, //当前课程详情页的课程id
                tabIndex: 2, // 当前选项卡显示的下标
                course_chapter: [],
                course: {
                    teacher: {}
                },
                playerOptions: {
                    playbackRates: [0.7, 1.0, 1.5, 2.0], // 播放速度
                    autoplay: false, //如果true,则自动播放
                    muted: false, // 默认情况下将会消除任何音频。
                    loop: false, // 循环播放
                    preload: 'auto',  // 建议浏览器在<video>加载元素后是否应该开始下载视频数据。auto浏览器选择最佳行为,立即开始加载视频（如果浏览器支持）
                    language: 'zh-CN',
                    aspectRatio: '16:9', // 将播放器置于流畅模式，并在计算播放器的动态大小时使用该值。值应该代表一个比例 - 用冒号分隔的两个数字（例如"16:9"或"4:3"）
                    fluid: true, // 当true时，Video.js player将拥有流体大小。换句话说，它将按比例缩放以适应其容器。
                    sources: [{ // 播放资源和资源格式
                        type: "video/mp4",
                        src: "http://img.ksbbs.com/asset/Mon_1703/05cacb4e02f9d9e.mp4" //你的视频地址（必填）
                    }],
                    poster: "../static/image/course-cover.jpeg", //视频封面图
                    width: document.documentElement.clientWidth, // 默认视频全屏时的最大宽度
                    notSupportedMessage: '此视频暂无法播放，请稍后再试', //允许覆盖Video.js无法播放媒体源时显示的默认信息。
                }
            }
        },

        components: {
            Header,
            Footer,
            videoPlayer, // 注册组件
        },

        filters: {
            // 格式化时间的过滤器
            format_time(val) {
                let timer = parseInt(val);
                if (timer < 10) {
                    timer = `0${timer}`
                }
                return timer
            }
        },

        created() {
            // 课程ID
            // this.get_course_detail();
            this.get_course_id();
            this.get_course_detail();
            this.get_course_chapter();
        },

        methods: {
            // 校验是否登录
            check_user_login() {
                let token = sessionStorage.user_token || localStorage.user_token;
                if (!token) {
                    this.$confirm('您尚未登录，请先登录官网！', '路飞学城官网温馨提示', {
                        confirmButtonText: '确定',
                        cancelButtonText: '取消',
                        type: 'warning'
                    }).then(() => {
                        this.$router.push('/login/');
                    });
                    return false;
                }
                return token
            },

            // 点击加入购物车
            addCart() {
                let token = this.check_user_login();
                this.$axios.post(`${this.$settings.Host}/cart/`, {course_id: this.course_id},
                    {headers: {'Authorization': 'jwt ' + token}}
                ).then((res) => {
                    this.$message.success(res.data.msg);
                    let cart_len = res.data.course_num;
                    // 通过 commit 来触发 store/index.js 中的
                    // mutations 下的 add_cart 方法对 vuex 中
                    // 存储的预购课中的课程数量进行更新
                    // （更新 state下cart中的cart_length）
                    this.$store.commit('add_cart', cart_len);
                }).catch((error) => {
                    this.$message.success(error.response.data.msg)
                })
            },

            // 当视频播放时，执行的方法
            onPlayerPlay(event) {
                alert("关闭广告")
            },

            // 当视频暂停播放时，执行的方法
            onPlayerPause(event) {
                alert("显示广告");
            },

            // 获取当前课程的id
            get_course_id() {
                let course_id = this.$route.params.id;

                course_id = parseInt(course_id);
                // course_id --> String
                if (course_id > 0) {
                    this.course_id = course_id;
                } else {
                    let self = this;
                    this.$alert('参数有误！', '别乱js填', {
                        callback() {
                            self.$router.go(-1);  //跳转回上一个页面
                        }
                    })
                }
            },

            // 获取课程详情数据
            get_course_detail() {
                this.$axios.get(`${this.$settings.Host}/course/detail/${this.course_id}/`)
                    .then((res) => {
                        this.course = res.data;
                        this.playerOptions.sources[0].src = res.data.course_video;
                        this.playerOptions.poster = res.data.course_img;

                        if (this.course.active_time > 0) {
                            let t = setInterval(() => {
                                if (this.course.active_time > 1) {
                                    this.course.active_time--;
                                } else {
                                    clearInterval(t);
                                }
                            }, 1000)
                        }
                    })
                    .catch((error) => {
                        console.log(error.response);
                    })
            },

            //获取章节数据
            get_course_chapter() {
                this.$axios.get(`${this.$settings.Host}/course/chapter/`, {
                    params: {
                        course: this.course_id,
                    }
                })
                    .then((res) => {
                        this.course_chapter = res.data;
                    })
                    .catch((res) => {
                        console.log(res.response);
                    })
            }
        },
    }
</script>

<style scoped>
  .main {
    background: #fff;
    padding-top: 30px;
  }

  .course-info {
    width: 1200px;
    margin: 0 auto;
    overflow: hidden;
  }

  .wrap-left {
    float: left;
    width: 690px;
    height: 388px;
    background-color: #000;
  }

  .wrap-right {
    float: left;
    position: relative;
    height: 388px;
  }

  .course-name {
    font-size: 20px;
    color: #333;
    padding: 10px 23px;
    letter-spacing: .45px;
  }

  .data {
    padding-left: 23px;
    padding-right: 23px;
    padding-bottom: 16px;
    font-size: 14px;
    color: #9b9b9b;
  }

  .sale-time {
    width: 464px;
    background: #fa6240;
    font-size: 14px;
    color: #4a4a4a;
    padding: 10px 23px;
    overflow: hidden;
  }

  .sale-type {
    font-size: 16px;
    color: #fff;
    letter-spacing: .36px;
    float: left;
  }

  .sale-time .expire {
    font-size: 14px;
    color: #fff;
    float: right;
  }

  .sale-time .expire .second {
    width: 24px;
    display: inline-block;
    background: #fafafa;
    color: #5e5e5e;
    padding: 6px 0;
    text-align: center;
  }

  .course-price {
    background: #fff;
    font-size: 14px;
    color: #4a4a4a;
    padding: 5px 23px;
  }

  .discount {
    font-size: 26px;
    color: #fa6240;
    margin-left: 10px;
    display: inline-block;
    margin-bottom: -5px;
  }

  .original {
    font-size: 14px;
    color: #9b9b9b;
    margin-left: 10px;
    text-decoration: line-through;
  }

  .buy {
    width: 464px;
    padding: 0px 23px;
    position: absolute;
    left: 0;
    bottom: 20px;
    overflow: hidden;
  }

  .buy .buy-btn {
    float: left;
  }

  .buy .buy-now {
    width: 125px;
    height: 40px;
    border: 0;
    background: #ffc210;
    border-radius: 4px;
    color: #fff;
    cursor: pointer;
    margin-right: 15px;
    outline: none;
  }

  .buy .free {
    width: 125px;
    height: 40px;
    border-radius: 4px;
    cursor: pointer;
    margin-right: 15px;
    background: #fff;
    color: #ffc210;
    border: 1px solid #ffc210;
  }

  .add-cart {
    float: right;
    font-size: 14px;
    color: #ffc210;
    text-align: center;
    cursor: pointer;
    margin-top: 10px;
  }

  .add-cart img {
    width: 20px;
    height: 18px;
    margin-right: 7px;
    vertical-align: middle;
  }

  .course-tab {
    width: 100%;
    background: #fff;
    margin-bottom: 30px;
    box-shadow: 0 2px 4px 0 #f0f0f0;

  }

  .course-tab .tab-list {
    width: 1200px;
    margin: auto;
    color: #4a4a4a;
    overflow: hidden;
  }

  .tab-list li {
    float: left;
    margin-right: 15px;
    padding: 26px 20px 16px;
    font-size: 17px;
    cursor: pointer;
  }

  .tab-list .active {
    color: #ffc210;
    border-bottom: 2px solid #ffc210;
  }

  .tab-list .free {
    color: #fb7c55;
  }

  .course-content {
    width: 1200px;
    margin: 0 auto;
    background: #FAFAFA;
    overflow: hidden;
    padding-bottom: 40px;
  }

  .course-tab-list {
    width: 880px;
    height: auto;
    padding: 20px;
    background: #fff;
    float: left;
    box-sizing: border-box;
    overflow: hidden;
    position: relative;
    box-shadow: 0 2px 4px 0 #f0f0f0;
  }

  .tab-item {
    width: 880px;
    background: #fff;
    padding-bottom: 20px;
    box-shadow: 0 2px 4px 0 #f0f0f0;
  }

  .tab-item-title {
    justify-content: space-between;
    padding: 25px 20px 11px;
    border-radius: 4px;
    margin-bottom: 20px;
    border-bottom: 1px solid #333;
    border-bottom-color: rgba(51, 51, 51, .05);
    overflow: hidden;
  }

  .chapter {
    font-size: 17px;
    color: #4a4a4a;
    float: left;
  }

  .chapter-length {
    float: right;
    font-size: 14px;
    color: #9b9b9b;
    letter-spacing: .19px;
  }

  .chapter-title {
    font-size: 16px;
    color: #4a4a4a;
    letter-spacing: .26px;
    padding: 12px;
    background: #eee;
    border-radius: 2px;
    display: -ms-flexbox;
    display: flex;
    -ms-flex-align: center;
    align-items: center;
  }

  .chapter-title img {
    width: 18px;
    height: 18px;
    margin-right: 7px;
    vertical-align: middle;
  }

  .lesson-list {
    padding: 0 20px;
  }

  .lesson-list .lesson-item {
    padding: 15px 20px 15px 36px;
    cursor: pointer;
    justify-content: space-between;
    position: relative;
    overflow: hidden;
  }

  .lesson-item .name {
    font-size: 14px;
    color: #666;
    float: left;
  }

  .lesson-item .index {
    margin-right: 5px;
  }

  .lesson-item .free {
    font-size: 12px;
    color: #fff;
    letter-spacing: .19px;
    background: #ffc210;
    border-radius: 100px;
    padding: 1px 9px;
    margin-left: 10px;
  }

  .lesson-item .time {
    font-size: 14px;
    color: #666;
    letter-spacing: .23px;
    opacity: 1;
    transition: all .15s ease-in-out;
    float: right;
  }

  .lesson-item .time img {
    width: 18px;
    height: 18px;
    margin-left: 15px;
    vertical-align: text-bottom;
  }

  .lesson-item .try {
    width: 86px;
    height: 28px;
    background: #ffc210;
    border-radius: 4px;
    font-size: 14px;
    color: #fff;
    position: absolute;
    right: 20px;
    top: 10px;
    opacity: 0;
    transition: all .2s ease-in-out;
    cursor: pointer;
    outline: none;
    border: none;
  }

  .lesson-item:hover {
    background: #fcf7ef;
    box-shadow: 0 0 0 0 #f3f3f3;
  }

  .lesson-item:hover .name {
    color: #333;
  }

  .lesson-item:hover .try {
    opacity: 1;
  }

  .course-side {
    width: 300px;
    height: auto;
    margin-left: 20px;
    float: right;
  }

  .teacher-info {
    background: #fff;
    margin-bottom: 20px;
    box-shadow: 0 2px 4px 0 #f0f0f0;
  }

  .side-title {
    font-weight: normal;
    font-size: 17px;
    color: #4a4a4a;
    padding: 18px 14px;
    border-bottom: 1px solid #333;
    border-bottom-color: rgba(51, 51, 51, .05);
  }

  .side-title span {
    display: inline-block;
    border-left: 2px solid #ffc210;
    padding-left: 12px;
  }

  .teacher-content {
    padding: 30px 20px;
    box-sizing: border-box;
  }

  .teacher-content .cont1 {
    margin-bottom: 12px;
    overflow: hidden;
  }

  .teacher-content .cont1 img {
    width: 54px;
    height: 54px;
    margin-right: 12px;
    float: left;
  }

  .teacher-content .cont1 .name {
    float: right;
  }

  .teacher-content .cont1 .teacher-name {
    width: 188px;
    font-size: 16px;
    color: #4a4a4a;
    padding-bottom: 4px;
  }

  .teacher-content .cont1 .teacher-title {
    width: 188px;
    font-size: 13px;
    color: #9b9b9b;
    white-space: nowrap;
  }

  .teacher-content .narrative {
    font-size: 14px;
    color: #666;
    line-height: 24px;
  }
</style>

